package dao.impl;

import dao.UserDao;
import pojo.User;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

public class UserDaoImpl implements UserDao {
        @Override
        public List<User> findAll() {
            List<User> list = new ArrayList<>();
            // TODO
            Connection connection = null;
            PreparedStatement preparedStatement = null;
            ResultSet resultSet = null;
            try {
                Class.forName("com.mysql.cj.jdbc.Driver");
                String url = "jdbc:mysql://127.0.0.1:3306/jdbc?characterEncoding=utf-8";
                try {
                    connection = DriverManager.getConnection(url, "root", "3390956");
                    // if(connection != null){
                    System.out.println("连接成功");
                    // }
                    //3.sql
                    String sql = "select * from user";
                    //4.预编译sql
                    preparedStatement = connection.prepareStatement(sql);
                    resultSet = preparedStatement.executeQuery();
                    //6.
                    while (resultSet.next()) {
                        User U = new User();
                        U.setId(resultSet.getInt("id"));
                        U.setName(resultSet.getString("name"));
                        U.setPass(resultSet.getString("pass"));
                        list.add(U);
                    }
                    return list;
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            } catch (ClassNotFoundException e) {
                throw new RuntimeException(e);
            } finally {

                try {
                    if (resultSet != null) {
                        resultSet.close();
                    }
                    if (preparedStatement != null) {
                        preparedStatement.close();
                    }
                    if (connection != null) {
                        connection.close();
                    }
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
        }
    }


